1. Field of the Invention
The invention relates generally to an apparatus for treating surfaces of wafer-shaped articles, such as semiconductor wafers, wherein one or more treatment fluids may be recovered from within a closed process chamber.
2. Description of Related Art
Semiconductor wafers are subjected to various surface treatment processes such as etching, cleaning, polishing and material deposition. To accommodate such processes, a single wafer may be supported in relation to one or more treatment fluid nozzles by a chuck associated with a rotatable carrier, as is described for example in U.S. Pat. Nos. 4,903,717 and 5,513,668. Such fluids can be liquids and/or gases supplied to the wafer-shaped articles.
Alternatively, a chuck in the form of a ring rotor adapted to support a wafer may be located within a closed process chamber and driven without physical contact through an active magnetic bearing, as is described for example in International Publication No. WO 2007/101764 and U.S. Pat. No. 6,485,531.
For many applications the closed process chamber needs to be purged with ozone or an inert gas such as nitrogen, prior to commencement of a given process, or between successive processes. Additionally, for many applications the process chambers also need to be cleaned, for example by rinsing with deionized water.
Designs for closed chamber single wafer wet processing are described in commonly-owned copending applications U.S. Pub. Nos. 2013/0134128 and 2015/0187629, in which the lid for the chamber is equipped with a structure for fluid distribution so as to purge the space between the magnetic ring rotor and chamber wall.
The present inventors have discovered that the functionality of existing closed chamber spin chucks is impaired by turbulence in the flow of fluids within the chamber, and especially in the bottom area of the chamber.